1. Field of the Invention
This invention relates to improvements in fluid pressure intensifiers and, more particularly, to hydraulic systems for boosting water pressure for cutting and cleaning applications.
2. Description of Related Art
At industrial sites such as refineries, shipbuilding and repair operations, need often arises for paint or contaminant removal and for cutting thick plate steel or concrete at remote sites. Conventional cleaning methods include sand and water blasting and metal-to-metal impact or scraping techniques, while cutting may be performed using acetylene torches and jackhammers. Sandblasting creates silicosis hazards for workers as well as environmental pollution, while torches and jackhammers leave jagged holes at best and create hazards to property and safety at times. Particularly where flammable liquids and gasses have been stored, such as in the holds of ships and barges, or in refinery storage tanks many feet in height and diameter, and where container walls may be half (1/2") inch steel plate or greater, combustion cutting, with acetylene torches or drilling and sawing where sparks are produced, may create hazards to human life and property. Likewise, paint removal and cleaning operations can generate such hazards if conducted using conventional scraping and polishing methods. Consequently, a need exists for a means of conducting non-combustion cleaning and cutting operations in such areas.
Water, with or without sand, is the preferred working fluid for non-combustion cleaning and cutting operations because it is abundant at most industrial sites and because it is relatively low in viscosity and non-flammable even under very high pressures. A number of devices available provide an apparatus for producing thin stream water for cutting, but many do not provide enough power to cut thick steel plate or thick concrete. It has been shown that cutting plate steel comparable to that used for such industrial application as mentioned above requires water pressures in excess of 30,000 pounds per square inch.
Further, those devices available that produce the necessary pressure often employ small piston and plunger type intensifiers that operate at such high frequency, and produce such a small displacement of water, that they require frequent maintenance or become unreliable after only a moderate number of hours of operation. If difficulties arise at remote sites, they often cannot be repaired without returning the device to a repair shop, thus requiring that the cutting operation be suspended until the unit is repaired, or requiring that a backup device be ready for the contingency. Thus, a need exists for a more reliable cutting apparatus which operates at a low enough cycle to minimize repair and maintenance, thereby having a high capacity factor (capacity factor is defined as the percent of time a device actually operates divided by the total time it could be operating if functioning properly at all times).
Often at such industrial sites, sources of power are limited. A device which requires electric power to function must be able to generate its own or it the power must be supplied at the site. In situations such as discussed above, for example, where piping and access doors may be required in an existing tank in a tank farm at a refinery, the work cannot be transported to a stationary site for cutting. Consequently, a need exists for a non-combustion cutting apparatus for such applications which is transportable.